How to group records based on array elements using mongodb?

@haylee.mertz 

To group records based on array elements in MongoDB, you can use the $unwind operator followed by the $group operator. Here's an example of how you can do this:

1. Use the $unwind operator to create a separate document for each element in the array:

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db.collection.aggregate([
  { $unwind: "$arrayField" }
])

1. Use the $group operator to group the documents based on the array elements and perform any aggregation operations needed:

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db.collection.aggregate([
  { $unwind: "$arrayField" },
  { $group: { _id: "$arrayField", count: { $sum: 1 } } }
])

In this example, arrayField is the field in your collection that contains the array you want to group by. The $unwind operator will create a separate document for each element in the array, and the $group operator will then group these documents based on the array elements and count the number of occurrences.

You can also perform other aggregation operations like calculating the average, sum, or any other operation inside the $group operator as needed.